Device and procedure for the regulation of the contact pressure of a winding bobbin

ABSTRACT

Device and process for the regulation of thread winding onto a bobbin by applying a desired contact pressure P c  of the operating bobbin, providing the bobbin-holder arm with a counterweighing counterthrust P p , on the basis of a pre-established trend of the value of P c  in relation to the advance length of the bobbin, indicating the weight of the bobbin in relation to the ratio between the length reached and indicating the rising a angle of the bobbin-holder arm, calculating the weight component due to the bobbin and said arm and applying a counterthrust P p  equal to the difference between said component and the pre-established value of the contact pressure P c  referred to the length reached.

The present invention relates to a device and procedure for regulatingthe winding of thread onto a bobbin to obtain the formation ofhigh-quality bobbins both with respect to form and winding density, inthe collection of yarn produced or processed by textile machines forbobbin winding. In industrial practice, the collection technique ofyarns is widely prevalent, by activating the rotation of a tube, madeidle by the mandrels of a bobbin-holder arm and pulling the yarn comingfrom a releasing organ to be wound thereon. The bobbin is thus formed bypulling and winding the yarn onto its surface, as it is entrained inrotation with an underlying motorized roll on which the bobbin itselfrests. This allows the yarn to be wound at a constant linear rate,regardless of the dimension of the bobbin with the advancing of thewinding, and only in relation to the rotation rate of said driving roil.During the formation of the bobbin, the bobbin-holder arm moves away andprogressively rises with respect to the motorized driving roll inrotation of the bobbin rotating around its hinging on the structure ofthe machine. The yarn is thus spirally wound onto the rotating bobbinand distributed with a backward and forward movement on its surface.

According to the necessities for the subsequent use of the yarn on thebobbin for processing downstream of the bobbin winding, the bobbin musthave a conical or cylindrical form, by winding it onto a conical orcylindrical tube. The driving rolls can also be conical or cylindrical.With reference to the scheme of FIG. 1, which illustrates the technicalproblem, in general, the distribution of the yarn on the bobbin iseffected by the same driving cylinder, which is processed withtraversing throats 17 which distribute the thread 18 with an axialbackward and forward movement on the surface of the bobbin 10, whereasthe driving cylinder 16 in rotation gives it the necessary drivingtorque for its winding. The number of traversing helixes situated on thebobbin driving cylinder 16, varies according to the titers and densitiesof the bobbin to be obtained.

The invention is described herein with reference to automatic bobbinwinders in the winding of thread onto a conical tube to form a conicalbobbin, moved with a driving roll having a straight cylindrical form,but with the specification that it can also be applied to bobbin windersin which straight cylindrical bobbins are formed, moved in rotation withconical or cylindrical rolls, and also for other textile machines inwhich the thread processed or produced upstream is collected on bobbins.

Bobbin winders generally consist of a series of heads or bobbin windingunits aligned along the whole front of the machine and equipped withcommon service equipment for their running; each of them is independentof the others and consequently. the bobbins in formation can havedifferent advance degrees in their winding. With reference to the schemeof FIG. 1, the bobbin 10 is held by the bobbin-holder arm 11 equippedwith two counterpoints 12, 13 which are engaged with the conical tube 14of the base of the bobbin. The conical bobbin in formation 10 rests andpresses on the driving roll or cylinder 16, driven by the motor M. Thetraversing throats 17 distribute the thread 18 with an axial backwardand forward movement on the bobbin. The bobbin 10 in formationprogressively increases in dimension and weight. The resting pressure ofthe bobbin on its collection cylinder 16 has a great influence on thedensity of the bobbin itself.

The technical problem towards which the present invention is directed isto obtain a good bobbin form, in the sides in the bottom and in the tip,and also in the correct packing of the yarn on its surface, byregulating the parameters which influence it.

Once a certain type of driving cylinder has been adopted—1,5-2-2,5-3helixes for each run—in relation to the titers processed and averagedensities required, the main winding parameters which influence thepacking of the yarn are the bobbin/cylinder pressure and the tension ofthe winding thread.

As far as the bobbin/cylinder pressure is concerned, each bobbin windingunit which forms the bobbin winder is equipped with its owncounterweighing device which regulates the pressure exerted by thebobbin on its driving or collection roll 16. The weight exerted by thebobbin on the cylinder derives from the bobbin-holder arm 11 and fromthe bobbin 10.

In general, the bobbin-holder arm 11 is a device which can be raised andlowered rotating around a fulcrum and which has its own invariable anddefined weight. The bobbin-holder arm is generally produced with aconsiderable weight to satisfy the requirements of stability andattenuation of the vibrations. The bobbin 10 also has its own weight,which increases as the winding proceeds and also contributes to theoverall resting pressure on the collection cylinder 16. Withoutcounterweighing, the contact pressure of the bobbin on the cylinderwould generally be excessive. When the bobbin is significantly deformedin its resting line on the cylinder, the thread is pulled at a lowerrate and deposited on the bobbin in its pressed generatrix and accordingto a much smaller diameter than the effective diameter of the bobbin,thus creating an uncontrolled tension on the wound yarn, which increaseson its own. In this case—even if not reaching the point of yarnbreakage—excessively hard bobbins would in any case be obtained and, inthe case of slippery yarns, due to the low friction between the woundcoils, there would be malformations of the sides of the bobbin, whoseinnermost layers tend to slip due to the pressure towards the ends.

In the known art, the remedy generally adopted is that ofcounterweighing by applying a force to the bobbin-holder arm whichcontrasts the weight of the arm and bobbin, with pneumatic devices ordevices with springs anchored on one side to the structure of themachine and on the other side to the bobbin-holder arm. The anchoringpoints are conceived so that, with the rotation of the bobbin-holder armbeing raised or lowered, the counterweighing torque can vary accordingto a certain law, with a variation in the force applied and/or of itsarm: once the application geometry has been determined, the course ofthe torque applied is established on the basis of the angle of thebobbin-holder arm. Said regulation system, for example that according topatent IT 1.231.742, which regulates the counterweighing force andcontact pressure on the basis of the value of the diameter of thegrowing bobbin, increasing the lifting force of the bobbin in a directratio with its diameter. This patent also envisages measuring thediameter on the basis of the ratio between the rotation rates of thebobbin and its driving cylinder. This system is not without drawbacks:for example, the system does not allow the value of the diameter withthe bobbin at a standstill to be known; furthermore its indications aremisleading during transitory regimes. The diameter to which said priordocument refers is the diameter of the deformed bobbin in its restinggeneratrix on the roll, and not its real diameter.

The basic criterion of the counterweighing pressure regulation is thatthe smaller the diameter, the less the bobbin-holder arm has to unload.If the bobbin is too compressed therefore and is deformed more thannecessary, the diameter indicated is even more reduced with respect tothe correct value and the bobbin-holder arm unloads even less: the erroris magnified. The reference to the mere diameter of the bobbin as theonly indicative parameter of its weight also leads to a furthersignificant imprecision, as the winding parameters, the yarn titer, thecross angle of the windings, the bobbin-winding tension and so forth,are not taken into consideration: i.e. it neglects the real density ofthe bobbin, to which the ratio between the real diameter and the weightof the bobbin should refer.

The present invention is defined in the first claim in its most generalmeaning of a regulation process of the form and density of the bobbinformed by the winding of yarn. Its variants or preferred embodiments aredefined in the dependent claims from 2 to 7.

The present invention is defined in claim 8 in its meaning of aregulation device of the form and density of the bobbin formed by thewinding of yarn. Its variants or preferred embodiments are defined inthe dependent claims from 9 to 11.

FIG. 1 illustrates the scheme—in a front view—of a thread collectionunit in an automatic bobbin winder and illustrates the technicalproblem.

FIG. 2 illustrates a scheme of a thread collection unit—in a perspectiveview and cross-section—of a bobbin-winding station, which indicates themost significant organs which intervene in the process and which formthe device according to the present invention for the control andregulation of the bobbin formation.

FIGS. 3 to 8 show illustrative diagrams of the weight trends and forceexerted as thrusts and counterthrusts exerted on the driving cylinderwith the proceeding of the bobbin winding, again calculated with respectto the length.

The regulation system of the formation according to the presentinvention, is based on the following logic. During the formation of thebobbin, when the titer of the yarn wound and winding parameters (numberof helixes on the driving cylinder and winding tension) are known, theprogressive weight of the bobbin P_(r) is indicated on the basis of thelength of thread wound, measured directly with the progressive number ofrevs of the driving cylinder 16 from the beginning of the bobbin, alsopossibly taking into account the weight of the empty tube 14. Thisweight is revealed with much more accuracy than what can be indicated bythe deformed diameter of the bobbin. The weight of the bobbin issubstantially concentrated on the driving cylinder and has a straighttrend with respect to the length indicated, as shown in FIG. 3.

According to the scheme of FIG. 2, again during the formation of thebobbin, the bobbin-holder arm 11 does not change its weight P_(b), but,as the winding proceeds, it changes inclination, passing from an initialα₀ for the empty tube to a progressively increasing a value. In thescheme of FIG. 2, the a angles are indicatively represented as theinclination with respect to the horizontal of the joining of the axis ofthe fulcrum 41 of the bobbin-holder arm 11 with the axis of the bobbin10.

As the bobbin increases, and with it the α angle, the weightdistribution of the bobbin-holder arm between its fulcrum 41 andpressure on the driving cylinder 16, varies: the part of weight P_(ba)of the bobbin-holder arm which is resting on the cylinder 16 decreaseswith an increase in the α, as illustrated in FIG. 4, which shows thetrend of the part of weight P_(ba) resting on the cylinder in relationto the thread length.

As for the most recently designed bobbin-winders, each bobbin-windingstation is equipped with its own control unit which individually governsthe winding operation: it is connected with the centralized control unitof the bobbin-winder receiving instructions and exchanging data andinformation.

According to the present invention, the control unit of the singlebobbin-winding station is equipped with a rev detector/counter 42 of thedriving cylinder; as indicated in FIG. 1, for example, the rev meter ofthe driving cylinder 16 is produced with a probe disk which generatesimpulses in a number proportional to its rotation, indicating the numberof impulses progressively received with a receptor 30 and transmittingthem, with a line 33, to the control unit of the single bobbin-windingstation. A measurer 34 of the rising α angle of the bobbin-holder arm isassociated with this.

Rev-counting devices are known in the art and can be produced withvarious techniques. A rev-counting device can be produced for example asa disk integral with the rotating part, as shown in FIG. 1—for examplewith a disk 29 fitted on the axis of the driving-cylinder 16 in FIG. 1,or on the bearing of the mandrel of the bobbin-holder arm—having anouter surface with N-S magnetic poles and a Hall effect probe suitablypositioned for detecting the passage of said rotating poles. With everypassage of a N polar expansion (or also the opposite S) the sensorgenerates an electric impulse, indicated by a sensor 30 and transmittedto the control unit with the line 33. As the number of poles arranged onthe circumference of the magnetic disk is known, it is possible, bycounting the number of impulses, to determine the number of revseffected.

On the basis of the formulations received, when the weight of thebobbin-holder arm and titer of the yarn being processed are known, thecontrol unit of the bobbin-winding unit is capable, with each indicationof the α angle and progressive revs effected by the cylinder 16, tocalculate the weight component (P_(r)+P_(ba)) which would be totallyresting on the driving cylinder 16, without the intervention of thecounterweighing device, which corresponds to the sum of the trends ofFIGS. 3 and 4 in relation to the length.

For each type of bobbin and yarn, the desired trend of the part ofweight resting on the driving cylinder in relation to the advancing ofthe bobbin, to obtain the optimum bobbin conformation, is experimentallyknown. FIG. 5, for example, shows desired trends of the resting forceexerted on the driving cylinder with the advancing of thebobbin-winding, calculated with respect to the length. In diagram A,relating to normal yarns, the desired value of the desired resting forceis constant at 100%, whereas in some cases, for example for elasticizedor low-friction yarns, the first winding layers must be much morecompact, so that they do not extend beyond the edges under the pressureof the upper layers which are wound over them. The trend of diagram B,specifically illustrates these types of yarns, for which after thewinding of the first 20-30% of bobbin length, a percentage decrease insaid resting force is required, which passes from the initial 100% tolower values. Depending on the type of yarn and destination of thebobbin, the bobbin-winding parameters are pre-selected for obtaining acertain winding density of the bobbin, experimented during the previousbobbin-winding operations.

According to the present invention, the desired trend of the contact orresting pressure P_(c), specific for the yarn and bobbin beingprocessed, again calculated with respect to the progressive length ofthe bobbin, is established at the beginning of the processing operationin the central unit of the bobbin-winder and transmitted thereby to thecontrol units of all the bobbin-winding stations or units.

The P_(p), or the counterthrust to be supplied with the piston of thecounterweighing device 44, is calculated each time by the control unitof the bobbin-winding unit as the differenceP _(p)=(P _(r) +P _(ba))−P _(c)   (a)between the total weight component due to the arm 11 and the bobbin 10which would be resting on the driving cylinder 16, without theintervention of the counterweighing device 44, and the weight or desiredresting pressure.

On the basis of the desired counterthrust value P_(p). the control unit48 of the bobbin-winding unit provides a command to a pressureregulating valve 46 which feeds the pneumatic counterweighing device 44.In the embodiment of FIG. 2, the pneumatic counterweighing deviceillustratively consists of a simple-effect piston 44 fed by aproportional regulator electrovalve 46 which determines the pressure ofthe service fluid to be supplied to said piston 44.

In the embodiment of the invention described so far, the value of the αangle is directly measured on the bobbin-holder arm 11 each time withthe angular sensor 34. According to an alternative embodiment of thepresent invention, described hereunder, the value of the α angle iscalculated instead on the basis of the length measured, thus reducingthe measuring to the sole detection of the revs progressively effectedby the driving cylinder. When the geometry of the bobbin-holder armsystem is known, the α angle value can be easily estimated bycalculation on the basis of the length wound which, when the windingdensity of the bobbin is known, corresponds to the volume of the woundbobbin. This calculation can be effected by the control units of themachine, for example the control unit 48 of the single bobbin-windingunit.

Illustratively referring, for example, to the cylindrical bobbin woundby the driving of a cylindrical roll, given the following sizes:

-   -   α: rising angle of the bobbin-holder arm    -   α₀: rising angle of said arm with an empty bobbin    -   Φ: diameter of the bobbin    -   Φ₀: diameter of the tube, i.e. of the empty bobbin    -   l: useful length of the bobbin-holder arm    -   L : bobbin length    -   ρ: density of the bobbin    -   s: gauge, or axial length, of the bobbin    -   Tit : yarn titer in m/g $\begin{matrix}        {{\alpha = {{a\quad{\tan\left( {\Phi/21} \right)}} - \alpha_{0}}}{wherein}} & (b) \\        {{\Phi = \sqrt{\frac{L}{{Tit} \cdot \left( {\rho \cdot \pi \cdot s} \right)} + \frac{\Phi\quad c^{2}}{4}}}{{and}\quad{therefore}}} & (c) \\        {\alpha = {{{a\quad{\tan\left( \frac{\Phi}{2 \cdot l} \right)}} - \alpha_{0}} = {{a\quad{\tan\left\lbrack \frac{\sqrt{\frac{L}{{Tit} \cdot \left( {\rho \cdot \pi \cdot s} \right)} + \frac{\Phi\quad c^{2}}{4}}}{2 \cdot l} \right\rbrack}} - \alpha_{0}}}} & (d)        \end{matrix}$        FIG. 6, on the other hand, illustratively shows the trend of the        α angle with respect to the horizontal plane in relation to the        length for conical bobbins.

The detection, calculation and command process for regulating theformation of the bobbin is effected as follows. The central control unit47 of the machine contains the constructive data—established unatantum—of the bobbin-winding station: for example the weight of the armP_(b), the diameter Ø_(c) of the driving cylinder, the ratio between thecounterweighing thrust P_(p) and pressure fed with the electrovalve 46.

Again on the control unit 47 of the bobbin-winder—at the beginning of anoperating cycle—the values of the bobbin-winding parameters areestablished for obtaining the desired density ρ, the yarn titer, andalso the final weight of the bobbin P_(f) i.e. of the final bobbinlength. The control unit of the bobbin-winder 47—again at the beginningof an operating cycle—sends the established values so far described tothe single control units 48, generally consisting of electronic cards,with which the bobbin-winding units forming the machine are equipped.

As already specified above, the desired trend D of the contact orresting pressure P_(c)—necessary for obtaining a bobbin having thedesired characteristics, specific for the yarn and bobbin beingprocessed, and as always calculated with respect to its progressivelength—is established at the beginning of the processing operation inthe central unit of the bobbin-winder and transmitted thereby to thecontrol units of all the stations or bobbin-winding units.

During the processing, each single bobbin-winding unit operatesautonomously and has a bobbin with its own advance degree, which candiffer from one to another, as also its control unit 48 controls itsbobbin in relation to its advancement. Said unit 48 receives impulses Fcorresponding to the revs effected by the driving cylinder, for examplegenerated by a probe disk, measures the metres of thread wound on thebasis of the impulses received and calculates the bobbin weight P_(r).

According to the two alternative embodiments described above, thecontrol unit of the bobbin-winding unit proceeds with the directdetection, or calculation on the basis of the length indicated, of therising a angle of the bobbin-holder arm.

From these two measurements, length wound and rising angle of thebobbin-holder arm, it then calculates the thrust on the driving cylinderdue to the weight P_(r) of the bobbin and the thrust P_(ba) on thecylinder due to the weight P_(b) of the bobbin-holder arm, whoseincidence varies with the lifting of the arm itself.

The control unit 48 of the bobbin-winding unit also knows thecounterthrust value P_(p) underway with the counterweighing piston onthe basis of the command signal provided in the previous regulation stepof the electrovalve 46; it is therefore capable of calculating the P_(c)resulting from the detections effected on the basis of the expression(a) and compares it with the value of P_(c) which is required as a basefor the present length parameter on the basis of the trend of thediagram established at the beginning of the bobbin-winding operation.

When the value of P_(c) previously provided significantly differs fromthe P_(c) value required on the basis of the new indication, the controlunit 48 of the bobbin-winding unit calculates the pressure to besupplied to the piston and sends the signal of the new pressure value tobe fed to the counterweighing device 44, to the electrovalve 46.

FIG. 7 illustratively shows the trend of the counterweighing force P_(p)in relation to the length, wherein the curve A refers to normal yarnsand the curve B refers to elasticized yarns. Analogously, FIG. 8illustratively shows the trend of the pressure in bar to be fed with theelectrovalve 44.

According to another embodiment variant of the present invention, the αangle value can either be directly detected and also calculated on thebasis of the length reached, comparing them with each other. When thetwo values differ considerably, the density of the bobbin beingprocessed differs from the desired density: if the α angle valuedetected directly significantly exceeds the calculated value, the bobbinis too soft and must increase its density and vice versa. The cause ofthis diversity can be sought locally for the single unit—for example annon-calibrated thread-tensioner—or for the whole bobbin-winder—forexample variations in the pressure of the service fluid distributed tothe thread-tensioner and/or counterweighing devices.

Once the hypothesis of an irregular parameter on the whole bobbin-winderhas been discarded, a possible remedy can consist in the localcorrection of the tension supplied to the thread: on the basis of thedifference in the α values, the control unit 48 of the bobbin-windingunit increases or reduces the thread tension to increase or decrease thedensity of the bobbin P_(r) to the desired value, processing and sendingthe relative command signal to the thread-tensioner not indicated in thefigure for the sake of simplicity.

According to a perfected embodiment of the process for regulating theformation of the bobbin according to the present invention, in therestarting phase of the bobbin, the value of P_(c) is increased to allowa better entrainment of the bobbin, reducing the slippages between thebobbin 10 and the driving cylinder 16, consequently reducing thecounterthrust P_(p) of the counterweighing device 44, with respect tothat of the regime regulation for the length reached. The reductionvalue of the thrust value (or counterthrust) P_(p) is within the rangeof 20%-60%, and preferably from 25% to 35%.

Apart from the structural winding elements of the bobbin alreadyillustrated above, the scheme of FIG. 1 indicates, for illustrative butnon-limiting purposes, the further components of the device according tothe invention for effecting the regulation process of the bobbinformation, the following components are shown in FIG. 2

-   -   pneumatic counterweighing device 44 connected to the        bobbin-holder arm 21, to be fed with a service fluid deriving        from its line,    -   electrovalve 46 for the feeding of the counterweighing device,    -   rev-counter sensor 42 of the revs effected by the driving        cylinder 30,    -   and angular sensor or detector 34 of the rising α angle of the        bobbin-holder arm,    -   electronic card 48, which forms the control unit of the        bobbin-winder station, connected to the control unit 47 of the        bobbin-winder, with the line 50, from which it receives the        established processing data, subsequently autonomously effecting        the phases of the regulation process described above during the        advancing of the bobbin,    -   connection line 33 of the impulse generator of the driving        cylinder with the electronic card 48 for counting the revs        effected by the driving roll 16,    -   connection line 35 of the detector 34 with the electronic card        48 for counting the rising angle α of the bobbin-holder arm 11,    -   connection line 51 of the electronic card 48 with the        electrovalve 46.

On comparing the regulation systems available in the known art, theprocess and device for regulating the bobbin formation according to thepresent invention offer considerable advantages. The weight of thebobbin is measured with great accuracy on the basis of the lengtheffectively wound and the yarn titer with a much higher precision thanthat allowed by the systems of the known art. The weight with which thebobbin-holder arm rests on the driving cylinder is distributed on thebasis of the effective lifting of the arm itself during the processingof the bobbin, detected and/or calculated on the basis of the length.

The determination of the advance degree of the bobbin and restingpressures. or weights of the bobbin-holder arm and bobbin in formation,as also the determination of their distribution on the driving cylinder,are not influenced by defects in the winding density. These operationscan be effected with the bobbin at a standstill or in movement.

1. A process for the regulation of the winding of the thread onto abobbin to obtain bobbins having the desired form and density, by theapplication of a desired contact pressure P_(c) of the bobbin (10) beingprocessed, by applying a counterthrust P_(p) to the bobbin-holder arm(11) provided by the counterweighing device (44), on the basis of apre-established trend of the value of P_(c) in relation to the advancedegree of the bobbin, characterized in that said pre-established trendof the contact pressure value P_(c) is calculated with respect to theadvance length of the bobbin and that during the formation of thebobbin, the device indicates the weight of the bobbin in formation P_(r)on the basis of the measurement of its length reached, it measures therising angle (α) of the bobbin-holder arm and, for each indication ofthe angle (α) and length reached of the bobbin in formation, itcalculates the total weight component (P_(r)+P_(ba)) which is resting onthe driving cylinder (16), applying a counterthrust P_(p) each time,calculated as the difference between said weight. component and thepre-established contact pressure value, according to the formulaP_(p)=(P_(r)+P_(ba))−P_(c) referring to the length reached.
 2. Theprocess for regulating the winding of the thread onto a bobbin accordingto claim 1, characterized in that the length reached by the bobbin information is detected on the basis of the number of progressive revseffected by the driving cylinder (16) starting from the beginning of thebobbin (10).
 3. The process for regulating the winding of the threadonto a bobbin according to claim 1, characterized in that the value ofthe rising angle (α) of the bobbin-holder arm (11) is measured directlyon said arm each time.
 4. The process for regulating the winding of thethread onto a bobbin according to claim 1, characterized in that thevalue of the rising angle (α) of the bobbin-holder arm (11) iscalculated on the basis of the length measured and corresponding to thevolume of the bobbin reached, the geometry of the system and the windingdensity of the bobbin being known.
 5. The process for regulating thewinding of the thread onto a bobbin according to claim 1, characterizedin that the value of the rising angle (α) of the bobbin-holder arm (11)is both detected directly on said arm and calculated on the basis of thelength reached, each time, subsequently comparing the two values and inthat, when said values differ significantly, the control unit (48) ofthe winding unit increases or reduces the thread tension to increase ordecrease the density of the bobbin ρ to the desired value, processingand sending the relative command signal to the thread-tensioner.
 6. Theprocess for regulating the winding of the thread onto a bobbin accordingto claim 1, characterized in that in the restarting phase of the bobbin,the value of P_(c) is increased, reducing the counterthrust P_(p) of thecounterweighing device (44), with respect to the regime regulation valuefor the length reached.
 7. The process for regulating the winding of thethread onto a bobbin according to claim 6, characterized in that thereduction value of the counterthrust value P_(p) is within the range of20% -60%, and preferably from 25% to 35%.
 8. A device for regulating thethread winding onto a bobbin to obtain bobbins having the desired formand density, by the application of a desired contact pressure P_(c) ofthe bobbin (10) being processed, comprising a counterweighing device(44) applied to the bobbin-holder arm (11) to provide a counterthrustP_(p), on the basis of a pre-established trend of the value of P_(c) inrelation to the advance degree of the bobbin, characterized in that saidpre-established contact pressure value P_(c) is calculated with respectto the advance length of the bobbin and in that the device comprisesmeasuring means (42) of the length reached for determining the weight ofthe bobbin in formation P_(r), means (34) for determining the risingangle (α) of the bobbin-holder arm (11) and means, at each detection ofthe α angle and length reached by the bobbin in formation, forcalculating the total weight component (P_(r)+P_(ba)) which is restingon the driving cylinder (16) without counterthrusts, each time applyinga counterthrust P_(p) with a counterweighing device (44) calculated asthe difference between said weight component and the pre-establishedvalue of the contact pressure, with the formulaP_(p)=(P_(r)+P_(ba))−P_(c) referring to the length reached.
 9. Thedevice for the regulation of the thread winding according to claim 8,characterized in that the measuring means of the length reached consistof a rev-counter devices of the progressive number of revs of thedriving cylinder (16) from the beginning of the bobbin.
 10. The devicefor the regulation of the thread winding according to claim 8,characterized in that the counterweighing device consists of asimple-effect piston (44) fed by an electrovalve (46) which determinesthe pressure of the service fluid to be supplied to the piston (44). 11.The device for the regulation of the thread winding according to claim8, characterized in that the determination of the rising angle (α) ofthe bobbin-holder arm (11) is effected by the control unit (48) of thebobbin-winding station by calculation on the basis of the lengthmeasured.